This invention relates generally to the shoe repair art and, more particularly, to an improved wearing surface portion for application to the underside of a shoe.
There have heretofore been proposed a number of types of repair soles for application to the worn underside of a shoe. Shoes have typically been "half soled" by removal of the original sole from the toe to the narrowed waist of the shoe, and sewing or gluing a new sole portion in place of the old. Leather or rubber soles of uniform thickness have generally been used for this purpose. U.S. Pat. No. 1,804,545 discloses a method for applying such soles, including beveling the underside of the new sole at a location adjacent the waist portion of the shoe. The beveled edge is tucked under a cut edge of the original sole which is similarly beveled, producing a sole of uniform thickness on the shoe. The sole of the '545 patent is applied with a waterproof adhesive material.
A specially formed repair sole for shoes is described in U.S. Pat. No. 2,016,070. It comprises a main portion of uniform thickness surrounded by a corrugated margin permitting outward extention of the repair sole to coincide with the outline of a sole to which it is applied. Although the final configuration of the repair sole thus depends upon the size of the shoe, the repair sole is not symmetric about a horizontal plane. In the fully extended condition of the corrugated margin, it is seen that the repair sole is formed with a flat adhesive coated surface for application to the original sole of the shoe being repaired. The additional thickness of the main portion is formed by providing additional material in the direction away from the shoe.
A patch for application to a worn portion of a shoe sole is disclosed in U.S. Pat. No. 2,040,001. The patch of the '001 patent is disclosed as covering only a small portion of a shoe sole. It has a flat upper surface and a curved lower surface such that the thickness of the patch tapers rather uniformly from its thickest region along one side thereof. The patch is intended to be placed with its thick region along one side edge of an old shoe sole, the tapered portions blending smoothly into the unworn portions of the original sole. The patch of the '001 patent may be either cemented or nailed in place.
However, the prior shoe repair structures described above suffer from a number of disadvantages. Primarily, shoe soles of uniform thickness fail to address the problem of highly nonuniform wear on the sole to which they are applied. In most cases, a shoe sole needing repair is worn to a greater extent at the center and the toe thereof than at other portions. A repair sole of uniform thickness simply conforms to this irregular wear pattern rather than correcting it. The only one of the discussed patents addressing itself even remotely to the problem of nonuniform wear is the '001 patent, and it is concerned only with covering an isolated portion of the shoe sole. In addition, it does not address the wear problem at the center and toe of the sole.
The repair structures of the listed patents also apparently fail to provide a suitable surface for providing a strong adhesive bond of the repair sole to the original shoe sole. In the case of the '545 patent, it is further necessary to remove the old sole and carefully prepare the shoe and the new sole. The preparation and application procedures would presumably require the labor of a skilled cobbler.
Finally, most prior shoe repair materials have been relatively expensive to produce and apply, and have often yielded less than satisfactory results.
Therefore, in many applications, it is desirable to provide an economical repair sole for shoes which can be easily applied to correct problems of undue wear in the central and toe portions of a shoe.